Hot swappable fracturing pump system

ABSTRACT

A system that permits fracturing pumps such as, for example, at least first and second fracturing pumps, each carried on a truck, to be connected to, and disconnected from, respective connection points on a fracturing manifold while fracturing fluid in the fracturing manifold is at pressure, in certain instances at or near fracturing pressure, and/or while other(s) of the fracturing pumps are being operated to pump fracturing fluid.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. patent application Ser. No.16/436,189, filed Jun. 10, 2019, the entire disclosure of which ishereby incorporated herein by reference.

TECHNICAL FIELD

The present disclosure relates to fracking and well workover operations.

BACKGROUND

A subterranean formation surrounding a well may be fractured to improvecommunication of fluids through the formation, for example, to/from thewell. Fracturing typically uses multiple high-pressure, high-flow pumpsto send high-pressure fluid downhole. The high-pressure and high-flowpumps are often plumbed to a manifold called a “missile” in a parallelconfiguration to achieve sufficient flow-rates and pressures to fracturethe formation. The pressure in the manifold, particularly duringfracking operations (i.e., frac pressure), is very high. If a leak wereto develop, or the equipment to fail, it could be injurious to personnelclose to manifold. The area near the manifold where a worker could beinjured is sometimes referred to as the “red zone.”

DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic diagram of an example well fracking site.

FIG. 2 is a schematic diagram of an example connection configurationthat can be used with aspect of this disclosure.

FIGS. 3A-3B are perspective views of an example connector shown closed(FIG. 3A) and open (FIG. 3B).

FIGS. 4A-4B are top-down views of the example connector of FIGS. 3A-3Bshown closed (FIG. 4A) and open (FIG. 4B).

FIG. 5 is a half side cross-sectional view of the example connector ofFIGS. 3A-3B in the closed position.

FIG. 6 is a partial perspective view of the example connector of FIGS.3A-3B with portions removed to show soft stops.

FIG. 7 is a side perspective view of the example connector of FIGS.3A-3B.

FIGS. 8A-8B is a perspective view and a half cross-sectional view,respectively, of an example drain assembly.

FIG. 9 is a block diagram of a controller that can be used with aspectsof this disclosure.

Like reference numbers in the various drawings indicate like elements.

DETAILED DESCRIPTION

During fracturing operations, the “missile” or frac manifold hasmultiple connected pumps. Typically, the entire system must bedepressurized to remove or change-out a pump, for example, if the pumpneeds maintenance, fails, or is no longer needed. The depressurization,disconnection, reconnection, and depressurization process can take asignificant amount of time. This disclosure describes an example systemthat allows disconnections/connections of pumps to the manifold to bemade without depressurizing the manifold and associated fluid lines. Inother words, pumps can be “hot swapped.” Moreover, the pumps can bedisconnected and connected without the need for personnel near the highpressure aspects of the manifold, i.e., without placing personnel in thedangerous “red zone.”

FIG. 1 is a schematic diagram of an example well site 1 arranged forfracking. The well fracking site 1 includes tanks 2. The tanks 2 holdfracking fluids, proppants, and/or additives that are used during thefracturing process. The tanks 2 are fluidically coupled to one or moreblenders 3 at the well site 1 via fluid lines (the one or more pipes,hoses, tubing and other types of fluid lines that define a fluid path).The blenders mix the fracking fluids, proppants, and/or additives priorto being pumped into the well 4. The blenders 3 are fluidically coupledto a fracturing manifold 7, or “missile.” One or more fracking pumps 5are also fluidically coupled to the manifold 7; for example, frackingpumps 5 a, 5 b, and 5 c may be fluidically coupled to the manifold 7, asshown in FIG. 1 . The manifold 7 routes the blended fluid to the pumps5, which then increase the pressure of the fluid to fracking pressure(i.e., the pressure at which the target formation fractures). Then, theflow from the pumps is comingled in the manifold 7 and directed into thewell 4. A data van 6 is electronically connected to the tanks 2, theblenders 3, the well 4, and the fracking pumps 5. The data van 6includes a controller 51 that controls and monitors the variouscomponents at the well site 1. The controller 51 is in communicationwith various component of the fracking site 1 through one or morecommunication links 53.

While a variety of components have been described in the example wellsite 1, not all of the described components need be included. In someimplementations, additional and/or different equipment may also beincluded. Also, the well 4 can be an onshore or offshore well. In thecase of an offshore well, including subsea wells and wells beneathlakebeds or other bodies of water, the well site 1 is on a rig or vesselor may be distributed among several rigs or vessels.

FIG. 2 is a schematic of an example fracturing manifold 7 with multipleconnection points 102 for connecting the fracking pumps 5, which areeach carried on a truck 8; for example, the fracking pumps 5 a and 5 bcarried on the trucks 8 a and 8 b, respectively, may each be connectedto one of the connection points 102. The manifold 7, itself, is oftenconfigured on a skid that can be transported as a unit or integratedwith a trailer that can be towed to the well site. The concepts hereinencompass a system that allows the fracturing pumps 5 to be connected toand disconnected from the fracturing manifold 7 while fracturing fluidin the manifold 7 is at pressure, in certain instances at or nearfracturing pressure, and/or while the other pumps 5 are being operatedto pump fracturing fluid. The fracking trucks 8 can back into aperspective location, and without a worker needing to be between thetruck and manifold 7, a pump 5 can be fluidically and mechanicallyconnected at a connection point 102. Similarly, when a pump 5 is to beremoved, the pump 5 can be disconnected from the manifold 7, and allowthe truck 8 leave the manifold 7, without a worker needing to be betweenthe truck and manifold. The workers do not need to physicallyconnect/disconnect hoses or make/break connectors when removing, addingor swapping pumps 5, allowing the workers can remain away from the “redzone.” In certain instances, the connection is made entirelyautomatically, without worker intervention.

As illustrated, the manifold 7 has multiple connection points 102 (twoshown, but in practice, many more are provided—often 14 to 20 arrangedon both sides of the manifold 7). The connection point 102 includes twosets of fluid lines—a high pressure side and a low pressure side. Thefluid line of the high pressure side has a high side valve 44, a bleedline 48 and a high side connector 106 and is connected to the highpressure fluid line 216. The high pressure fluid line 216 is fluidicallycoupled to the well. It collects pumped fluid from each pump 5 anddirects the pumped fluid to the well. The fluid line of the low pressureside has a low side valve 46 and a low side connector 112, and isconnected to the low pressure fluid line 218. The low pressure fluidline 218 is fluidically coupled to the blender. It directs the blendedfrac fluid to the pumps 5 so that the fluid can be pumped. The high sidevalve 44 can be closed to seal against pressure in the manifold 7 in thehigh pressure line 216 to the well, thus isolating the connection point102 from the pressure in the manifold 7 produced by the other connectedpumps. The low side valve 46 can be closed to seal against pressure inthe manifold 7 in the low pressure line 218 from the blenders, thusisolating the connection point 102 from the low pressure supply of fracfluid. The valves 44, 46 can be manual or, in certain instances, eitheror both can be actuable in response to a signal to open/close. Actuablevalves 44, 46 enable the operation to be controlled by the controller51. Bleed line 48 enables draining high pressure fluid between the valve44 and high side connector 106. The bleed line 48 can be integrated withthe valve 44, the high side connector 106 or can be valved in the linebetween the two. In certain instances, the bleed line 48 is actuable toopen in response to a signal (e.g., by use of an actuable valve). Also,while the connection point 102 has been illustrated and described ashaving a single valve for each of the high and low pressure sides,alternative or additional valve configurations can be used withoutdeparting from this disclosure. For example, particularly on the highpressure side, a second valve can be included in series with the firstvalve. Adding a second valve in series with the first valve allows for adouble block and bleed or a double block and monitor configuration.

The high pressure side connector 106 is configured to connect/disconnectthe discharge line 12 b (i.e., discharge) of a pump 5 on a frack truck 8to the manifold 7. When connected, the high pressure side connector 106secures to and seals with the discharge line 12 b, and is capable ofhandling the high pressure provided by the pump 5 during the fracturingtreatment. In certain instances, the high side connector 106 is actuablein response to a signal to connect/disconnect, which enables theoperation of the high side connector 106 to be controlled by thecontroller 51. The low pressure side connector 112 can be the same typeof connector as the high side connector 106 or another type ofconnector. Typically, though, the low pressure side connector 112 needonly be configured to seal to the lower pressure of the low pressureline 12 a (i.e., suction) of the pump 5 (and not the high pressureproduced by the pump 5 or in the manifold). As discussed in more detailbelow, in certain instances, the low pressure side connector 112 is amale or female stab type connector. The connectors 106, 112 can bemounted at a specified height off the ground to align to the fluid linesfrom the pump 5. In some implementations, one or both of the connectors106, 112 can be mounted on an adjustable platform that can be adjustedto suit different configurations of trucks.

As illustrated, a first high pressure side pressure sensor 210 a ispositioned to sense internal pressure on the side of the valve 44attached to the high side connector 106. A second high pressure sidepressure sensor 210 b detects internal pressure on a side of the valveexposed to the pressure within the high pressure line 216 of thefracking manifold 7. A similar arrangement of pressure sensors areprovided on the low pressure side, with a first low pressure sidepressure sensor 212 a positioned to sense internal pressure on the sideof the valve 46 attached to low side connector 112. A second lowpressure side pressure sensor 202 b is positioned to detect internalpressure on a side of the valve exposed to pressure within the lowpressure line 218 of the fracking manifold 7. In certain instances, thepressure sensors 210 a, 210 b, 212 a, 212 b can be used to implementelectronic interlocks to prevent the valve 44 and/or valve 46 from beingopened under pressure or the high side connector 106 and/or low sideconnector 112 from disconnecting under pressure. For example, dependingon the formation, frac pressure in the high pressure fluid line 216 canreach 15 thousand pounds per square inch (ksi) or more. If thecontroller 51 detects, with the second pressure sensor 210 b, such ahigh pressure and detects, with the first pressure sensor 210 a, a muchlower pressure (e.g., near atmospheric), then controller 51, based onoutput from the sensors 210 a, 210 b can effectuate an interlock toprevent the valve 44 from opening. After a fracturing pump at theconnection point 102 has been pressurized, the first pressure sensor 210a and second pressure sensor will detect similar pressures, and thecontroller may allow valve 44 to open, but prevent the high sideconnector 106 from disconnecting. The pressure differential threshold atwhich the controller 51 effectuates the interlock of the valve 44 can bespecified to the controller 51. Similarly, the pressure threshold, overwhich the controller 51 prevents operation of the connector 106 can alsobe specified to the controller 51. More details on example interlocksare described throughout this disclosure.

In some implementations, the high side connector 106 includes a guidecone 110 mounted to a housing of the high side connector 106. The guide110 guides the discharge line 12 b of the fracturing pump 5 align withthe high side connector 106. For example, in instances where thefracturing pump 5 is mounted to a fracturing truck 8, the truck 8 canback up to the fracturing manifold 7 and “stab” the discharge line 12 binto the connector 106. The guide 110 has a conical funnel shape thathas a narrower end nearer the connector 106 and a wider end opposite thenarrower end. The conical shape of the guide 110 drives the dischargeline 12 b into concentric alignment with the high side connector 106,allowing the discharge line 12 b to be concentrically received withinthe connector 106. While described primarily with a funnel shape, othershapes (e.g., pyramidal or other) or other guidance features can be usedwithout departing from this disclosure. In certain instances, thedischarge line 12 b or connection point 102 can have an in-line flexcoupling or otherwise have flexibility to enable flex to account formisalignment when the discharge line 12 b is stabbed into the high sideconnector 106. Thus, the truck 8 with the pump 5 will need to back intoproximity to the connection point 102, but need not precisely positionwith respect to the high side connector 106. In certain instances, thedischarge line 12 b and suction line 12 a can be affixed, relative toone another, near their free ends by a strut or some other structure, sothat when the discharge line 12 b has been concentrically aligned by theguide cone 110, the position of the suction line 12 a is likewiseconcentrically aligned to stab into the low side connector 112 as thedischarge line 12 b stabs into high side connector 106. Such anarrangement can be implemented with only the guide cone 110 on the highside connector 106, and no guide cone on the low side connector 112.Although not shown in FIG. 2 , the low pressure side can, in certaininstances, have a guide cone 110 on low side connector 112 to facilitatealignment of the suction line 12 a with low side connector 112.

In certain instances, the hardware of the connection points 102,including the valves 44, 46, the connectors 106, 112, the sensors andother related components can be mounted on a trailer or skid 220separate from the manifold 7. The skid 220 can be set beside themanifold 7, and fluid connections made-up between the fluid lines on theskid 220 and the manifold 7 to establish the connection points 102 asconnection points to the manifold 7. The hardware for each connectionpoint 102 can be on a separate skid 220, or a single skid 220 can carrythe hardware for more than one connection point 102. For example, incertain instances, a skid 220 may carry the hardware for a pair ofconnection points 102. In certain instances, one, two or three skids maycarry the hardware for all the connection points 102 on one side of themanifold 7. Other configurations are contemplated. In certain instances,the hardware of the connection points 102 is partially or whollyintegrated with the manifold 7, so that the skid or trailer carrying themanifold 7 likewise carries the hardware for some or all of theconnection points 102.

The high pressure side connector 106 can take a number of differentforms. For example, the high side connector 106 can be an iris type,with clamps that move on a spiral type path inward to effectuateclamping. In another instance, the high side connector 106 can be a camactuated or rotational actuated type connector, a gate action connector(where one part swings over a shoulder an another part and locks), anotch connector (where a latching component is laid into a notch thatlocks it in place) or an internal latch (with an expanding latch thatgrips an internal profile. Other connector configurations are possible,and contemplated herein.

In certain instances, only the pump discharge line 12 b is stabbed intothe connection point 102, and the pump suction line 12 a is connectedmanually, using a length of hose with a manual connector 112 on its endthat extends from the connection point 102 and is long enough to enablea worker making the connection to remain a safe distance from the highpressure of the manifold 7. In other words, the hose is long enough toallow the worker to make the connection while staying out of the “redzone.” In certain instances, the low pressure side connector 112 is astab connector—where a machined female bore internally receives andseals with a male stab. Typically the male stab includes seals that sealto the side wall of the inner female bore, but in certain instances, theseals could be provided on the female bore. The male stab can beprovided on suction line 12 a and the female provided as connector 112or vice versa. In such a case, the low side connector 112 can rely onthe high pressure side connector 106 to secure the male stab axially inthe stab receptacle.

While illustrated and described as being at the manifold 7, similarconnection points 102 can be included elsewhere within the fracturingsite 1, such as at the fluid lines of fracturing tanks, blender, andelsewhere. Such connection points 102 allow components to be added andremoved to the system quickly without depressurizing system components.

FIGS. 3A-3B are perspective views of an example connector 302, which canbe used as high side connector 106, shown closed/engaged (FIG. 3A) andopen/disengaged (FIG. 3B). The connector 302 is actuable in response toa signal (e.g., hydraulic, electric and/or other) to secure (i.e., lock)a tool to the fracturing stack 200 as well as any tools and other stackcomponents positioned above the connector 302, such as the lubricator202 or BOP 204. The connector 302 includes a housing 304. The housing304 carries a drive ring 306 that is rotatable relative to the housing304. The housing 304 receives a first line 310 from the manifold and asecond line 312 from the pump 5 (e.g., discharge line 12 b or suctionline 12 a), such that the housing is positioned around the lines. Asillustrated, the drive ring 306 protrudes outward from an outerperimeter of the housing 304. One or more clamps 308 (six are shown—eachdefining an arc segment of a circle) are within the housing to clamp tothe lines 310, 312. Each clamp 308 includes an attachment end 308 a anda clamping end 308 b. The clamp 308 is movable between an engagedposition (FIG. 3A) and a disengaged position (FIG. 3B). In the engagedposition, the clamp 308 engages the second line 312 by the clamping end308 b. In the disengaged position, the clamp 308 allows the well tool tobecome unrestrained from the connector 302.

A linkage 402 is coupled to the drive ring 306, the housing 304, and theclamp 308. The linkage 402 is movable between a first positionsupporting the clamp in the engaged position (FIG. 3A) and a secondposition supporting the clamp in the disengaged position (FIG. 3B). Thelinkage 402 is movable between the first position and the secondposition by rotating the drive ring 306.

FIGS. 4A-4B are top-views of the example connector of FIGS. 3A-3B. Asillustrated the connector has multiple linkages, one for each clamp. Insome implementations, additional or fewer clamps and linkages can beused. In general, the linkages are configured to move concurrently withone another. For example, the linkages 402 are shown as all beingcoupled to the same drive ring 306.

Each of the linkages includes a first arm 404 with a first end 404 a anda second end 404 b. The first end 404 a of the first arm 404 is hingedlycoupled to the housing 304. That is, the first end 404 a of the firstarm 404 has a single degree of freedom to rotate about a pivot pointfixed to the housing 304. This single degree of freedom is in the sameplane as the drive ring 306. A second arm 406 has a first end 406 a anda second end 406 b. The first end 406 a of the second arm 406 ishingedly coupled to the drive ring 306. That is, the first end 406 a ofthe second arm 406 has a single degree of freedom to rotate about apivot point fixed to the drive ring 306. This single degree of freedomis in the same plane as the drive ring 306. The second end 406 b of thesecond arm 406 is hingedly coupled to the second end 404 b of the firstarm 404. The clamp 308 is coupled to the second end 404 b of the firstarm 404 and the second end 406 b of the second arm 406. The attachmentend 308 a of the clamp 308 is coupled to the second end 404 b of thefirst arm 404 and the second end 406 b of the second arm 406.

The drive ring 306 is coupled to an actuator 408 configured to operatein response to a signal. In some implementations, the actuator 408 is arotary actuator. In such instance, the drive ring 306 can includemultiple teeth on an outer circumference of the drive ring 306. Theteeth can engage with a pinion gear on the rotary actuator 408, whichthe rotary actuator 408 rotates to drive rotation of the drive ring 306.In some implementations, the drive ring 306 can be coupled to a separatedrive gear surrounding the first line 310 or the second line 312. Theseparate drive gear can then be coupled to the actuator 408. In someimplementations, a chain drive can be used to connect the actuator gearto the drive ring or the drive gear. In some implementations, all orpart of the gearing system may be retained and protected within thehousing 304. In some implementations, the actuator 408 can be a linearactuator. In such an implementation, the actuator is attached directlyto the drive ring 306 by a linkage, such that when the actuator 408extends, linearly, it rotates the drive ring 306.

FIG. 5 is a side cross-sectional view of an example connector in theclosed position. The first line 310, the second line 312, and thehousing 304 are aligned on a common center axis 502 (i.e., concentric),and the line 312 has a male stab 514 that is received and sealed in afemale receptacle 512 of line 310 (or vice versa). The drive ring 306 isrotatable about the common center axis 502. As illustrated, the firstline 310 and the second line 312 have hubs 508 a, 508 b at their endsthat form a male profile 504 when mated together and the first line 310stabs into the second. The clamps 308 each have a female profile 506shaped to receive the male profile 504. The combination of profilesallows the connector to lock the first line 310 and the second line 312together, as the female profile 506 axially bounds the male profile504—holding the two lines 310, 312 axially together—and the clamps 308circumferentially enclose the male profile 504—laterally holding the twolines 310, 312 together.

In some implementations, a pressure port 508 in the first line 310communicates to the interior bore of the lines 310, 312. A pressuresensor connected at this pressure port 508 can sense the pressure withinthe interior bore of the lines 310, 312.

As shown in FIG. 6 , the latch 308 can include one or more bumpers orstops 510 to limit the motion of the clamps 308. The stops 510 areaffixed to the housing 304 and are positioned relative to each clamp 308such that when the clamp 308 is fully disengaged from the lines 310, 312the clamp 308 abuts the stops 510. The stops 510 align the clamp 308relative to the center axis 502, with the center of clamp's arc segmentbeing near or at the center axis 502. The stops 510 can be secured tothe housing 304 in a variety of ways, such as being fastened to a topcover (not shown) of the housing 304. In some implementations, two softstops 510 are used for each clamp, but additional or fewer stops can beused.

FIG. 6 illustrates a side perspective view of the connector 302 with aguide cone 602 that funnels the second line 312 to concentrically alignon the center axis 502 as it is stabbed into the guide cone 602 and theninto the first line 310. The guide cone 602 is suitable for use as guidecone 110 (FIG. 2 ).

FIG. 7 also shows a system of proximity switches 604 to detect theopen/closed/intermediate state of the connector 302. The proximitysensors 604 are mounted on the housing 304 to sense the position of acorresponding magnet 608 affixed to the drive ring 306. When the drivering 306 is rotated to engage the clamps to the first and second line310,312, the magnet 608 is adjacent one proximity sensor 604 and whenthe drive ring 306 is rotated to disengage the clamps, the magnet 608 isadjacent the opposing proximity sensor 604. As discussed below, acontroller can determine the state of the latch using the proximitysensors 604 and, in turn, operate an electronic interlock.

FIG. 7 also shows a drain assembly 606 that extends through the side ofthe housing 304. The drain assembly 606 can operate as bleed 48 (FIG. 2). The drain assembly 606 protrudes into the bore of the connector 302to be in fluid communication with the bores of the first and secondlines 310, 312, and can be actuated open to drain fluid from the bore oractuated closed to seal against draining fluid. Thus, the drain assembly606 can be used to equalize pressure between the central bore and theoutside environment.

FIGS. 8A-8B are a perspective view and a half cross-sectional view,respectively, of an example drain assembly 606. The example drainassembly includes a drain valve 702 and a hydraulic interlock 704. Thehydraulic interlock 704 includes a push button valve 703—a type of valvewith a hydraulic input 706, a hydraulic output 708 and a valve statepush button 710 that, when pushed in, opens the valve to pass fluidbetween the input 706 and output 708 and that, when not pushed in, sealsagainst passage of fluid between the input 706 and output 708. In use,the valve 702 is connected between the hydraulic pump that would, inother circumstances, supply hydraulic pressure to power ahydraulic-driven, drive ring actuator used to operate the connector 302.Thus, the hydraulic input 706 is connected to the hydraulic pump whilethe hydraulic output 708 is connected to the hydraulic actuator (e.g.,actuator 408 of FIG. 4A). The valve state button 710 interacts with atab 712 on the drain valve 702. When the drain valve 702 is in a closedposition, the tab 712 abuts and presses against the valve state button710. The pressure applied by the tab 712 on the valve state button 710,pushes the button 710 in and puts the valve in a closed state. In theclosed state, hydraulic fluid is sealed against passing from the input706 to output 708, and onward to drive the drive ring actuator. In thisstate, the actuator for the drive ring can receive no pressure and theconnector 302 is locked out and cannot operate to open. When the drainvalve 702 is in an open position, the tab 712 is moved from the valvestate button. The valve state button 710 is allowed to protrude outward,and the valve 702 moves to an open state. In the open state, hydraulicfluid can pass between input 706 and output 708 and onward to drive thehydraulic actuator. In this state, the actuator for the drive ring isable to receive hydraulic pressure and can be operated to open. In someimplementations, an electrical proximity switch 714 can be includedsignal a state of the drain valve 702, the hydraulic interlock 704, orboth.

Referring to FIG. 8B, the operation of the drain valve 702 is described.An end portion of the drain valve 702 is inserted through an aperture inthe sidewall of the housing 304 of connector 302, so that a plunger 758of the valve 702 is in the bore of the housing. The outer surface of thedrain valve 702 has seals 764 that seal to the inner diameter of theaperture, sealing the drain valve 702 to the housing. The drain valve702 is secured to the housing 304 with threads 760. When the drain valve702 is in a closed position (as illustrated), the plunger rests on aseat 762. The seat 762 seals against passage of fluid into an interiorcavity 768 of the valve 702. The seat 762 can be a metal-to-metal seat,an elastomer seat, or another type of seat. When the drain valve 702 isin an open position, the plunger 758 is moved apart from the seat 762 bythe valve stem 756. Separating the plunger 758 from the seat 762 allowsfluid to flow from the central bore of the housing 304, through thecavity 768 to an outlet 770. The movement of the valve stem 756 toopen/close the plunger 758 is controlled by an actuator. In FIG. 8B, theactuator is a hydraulic actuator that includes a pressure inlet 750configured to be connected to a hydraulic source, such as the hydraulicpump connected to the valve of the interlock 704 or another source, andwhich itself may have a control valve to gate pressure to the inlet 750.The pressure inlet 750 is fluidically connected to a spring-loadedpiston 752 affixed to the valve stem 756. When pressure is appliedthrough the inlet 750, it acts on the piston 752 driving it toward theright in FIG. 8B. The piston 752, in turn, also drives the valve stem756 to the right, opening the valve 702 by moving the plunger 758 offthe seat 762. The spring-loaded piston is biased to the left in FIG. 8 b, so as to cause the valve 702 to “fail closed.” That is, when there isno hydraulic pressure at the pressure inlet 750, the spring 754 of thespring-loaded piston 752 will force the drain valve 702 into the closedposition shown in FIG. 8B.

Although described with the hydraulic interlock above, the connector 302can be alternatively or additionally implemented with an electronicinterlock. For example, a controller (e.g., controller 51) can monitorpressure in the central bore (e.g., via a pressure sensor in port 508 orelsewhere). If pressure above a threshold pressure is sensed in thebore, the controller can refuse to actuate the connector 302 to open(e.g., refuse to signal actuator 408 to operate) until the pressuredrops below the threshold pressure.

As shown in FIG. 9 , the well fracking site 1 can include a controller51 to, among other things, monitor pressures of the operating volumesand send signals to actuate valves and/or connectors. As shown in FIG. 9, the controller 51 can include a processor 1002 (implemented as one ormore local or distributed processors) and non-transitory storage media(e.g., memory 1004—implemented as one or more local or distributedmemories) containing instructions that cause the processor 1002 toperform the methods described herein. The processor 1002 is coupled toan input/output (I/O) interface 1006 for sending and receivingcommunications with other equipment of the well fracking site 1 (FIG. 1) via communication links 53 (FIG. 2 ). In certain instances, thecontroller 51 can communicate status with and send actuation and controlsignals to one or more of the connectors 106, 112, the valves 44, 46 andother valves, including main valves and a swab valve of a fracturingstack, a BOP, a lubricator (and its tool trap), a well drop launcher, aswell as various sensors (e.g., pressure sensors, temperature sensors andother types of sensors) at the well site. In certain instances, thecontroller 51 can communicate status and send actuation and controlsignals to one or more of the systems on the well site 1, including theblenders 3, fracking pumps 5 and other equipment on the well site 1. Thecommunications can be hard-wired, wireless or a combination of wired andwireless. In some implementations, the controller 51 can be locatedremote from the manifold, such as in the data van 6, elsewhere on thewell site 1 or even remote from the well site 1 (e.g., at a centralmonitoring facility for monitoring and controlling multiple well sites).In some implementations, the controller 51 can be a distributedcontroller with different portions located about the well site 1 or offsite. For example, in certain instances, a portion of the controller 51can be distributed among individual connection points 102, while anotherportion of the controller 51 can be located at the data van 6 (FIG. 1 ).

The controller 51 can operate in monitoring, controlling, and using thewell fracturing site 1 for introducing or removing high pressureequipment from the manifold 7. To monitor and control the manifold 7,the controller 51 is used in conjunction with sensors to measure thepressure of fluid at various connection points of the manifold 7. Inputand output signals, including the data from the sensors and actuators,controlled and monitored by the controller 51, can be loggedcontinuously by the controller 51.

For example, an operator, via the controller 51, can orchestrate theconnection/disconnection/swap of a pump 5 at a connection point 102 ofthe manifold 7 (FIG. 2 ). Notably, the human operator can operate thecontroller 51, and thus the resulting physical steps, at a safe distancefrom the high pressure lines, far enough that if there were a highpressure leak or failure, the operator would not be injured. Theoperation can be effectuated via a terminal or other control interfaceassociated with the controller 51. In certain instances, the operator,via controller 51, actuates a fully automated sequence run by thecontroller 51 to perform the below described steps (i.e., the operatorjust presses start, or similar, and the controller 51 performsautonomously). Alternatively, the operator, via controller 51, commandsone or more of the individual, below described steps. In eitherinstance, the terminal can present menu items to the operator thatpresent the operator's options in commanding the controller 51.

If the manifold 7 is at pressure, for example, with one or more of thepumps 5 connected to the manifold 7 pumping at frac pressure or at someother pressure, the manifold 7 need not be depressurized to connectanother pump 5. When the manifold 7 is at pressure and no pump isconnected to a certain connection point 102, the high side valve 44 andlow side valve 46 of that connection point 102 are in a closed position.The truck 8 with the pump 5 is backed up to the connection point 102,and the pump discharge line 12 b and pump suction line 12 a areconnected to their respective corresponding lines at the connectionpoint 102. In certain instances, backing the truck 8 up to the manifold7 stabs the pump discharge line 12 b and the pump suction line 12 a intotheir respective counterparts at the connection point 102. In instanceswhere the low pressure side includes a length of hose with a manualconnector 112 on its end, such a manual connection can be made beforethe truck 8 is fully positioned to stab the discharge line 12 b into itscounterpart at the connection point 102, or could be made after.

Thereafter, the controller 51 signals the high side connector 106 toactuate closed, securing and sealing the discharge line 12 b to itscounterpart at the connection point 102. If the low side connector 112at the suction line 12 a is an actuable connector (as opposed to thestab receptacle, described above, or a manual connector), the controller51 signals the low side connector 112 to actuate closed, securing andsealing the suction line 12 a to its counterpart at the connection point102.

The controller 51 then actuates the valves 44 and 46 to open. Typically,the valve 46 on the low pressure side is opened first. This allows thepump 5 to be operated to bring pressure in the discharge line 12 b up tothe pressure or near the pressure in the manifold 7. After verifying thepressure is equalized across the valve 44, the controller 51 signals thevalve 44 to open. The controller 51 can determine the pressures oneither side of the valves 44 and 46 by receiving signals from thepressure sensors 210 a, 210 b on the high pressure line and sensors 212a, 212 b on the low pressure line. For example, if the pressuredifferential, as determined from sensors 210 a and 210 b, is above athreshold differential, the controller 51 will not allow valve 44 on thehigh pressure side to open. The threshold differential, in certaininstances, is determined to ensure the valve 44 does not open in anunsafe condition.

With the valves 44, 46 open, the pump 5 can be operated to pump fracfluid received through the suction line 12 a to the discharge line 12 b,into the manifold 7 and on to the well. In certain instances, thecontroller 51 can be coupled to the pump 5 to actuate the pump to beginand stop pumping, control its rate and control other operationalcharacteristics of the pump 5.

If a pump 5 needs to be removed from the manifold 7 while the manifold 7is at pressure, for example if the pump 5 needs maintenance or fails oris no longer needed in the operation, the pump 5 is shut down and thecontroller 51 actuates the valve 44 on the high pressure side to closeand then actuates the valve 46 on the low pressure side to close.Thereafter, the controller 51 actuates the bleeds 48 on both the highand low pressure sides to open and depressurize the suction line 12 aand discharge line 12 b. The controller 51 monitors pressure at leastvia pressure sensor 210 a, to determine whether the pressure has droppedbelow a specified threshold pressure before actuating connector 106 tothe discharge line 12 b open and release the pump 5 from the connectionpoint 102. The specified threshold pressure can be selected to ensurethat the connector 106 does not open in an unsafe condition. Ininstances where the low side connector 112 is actuable, the controller51 can monitor pressure via the pressure sensor 212 b and compare thepressure to a second threshold pressure before actuating low sideconnector 112 to open. Once disconnected, the truck 8 carrying the pump5 can drive off. Another pump 5 can be connected to the manifold 7 atthe empty connection point 102 without depressurizing the manifold 7, asdescribed above.

The concepts described herein can, in certain instances, yield a numberof advantages. For example, the operations can manifest a significanttime, and thus cost, savings because, the fracturing equipment,including the manifold and associated lines, need not be pressured upand down to remove, add or change out a pump. Furthermore, pressuretesting between replacing pumps can be reduced or eliminated. Costsavings can be had in fuel/energy, operator and equipment costs thatwould otherwise have been incurred in pumping the well and such a largevolume of the fracking stack, manifold and related equipment up topressure, both for pressure testing and pressurizing back up tofracturing pressure in performing the fracturing. Savings due to wear onequipment can also be realized, as the maintenance (e.g., repair of wornparts and greasing) on the surface equipment is reduced due to thereduction in pressure cycling. Finally, savings can be realized inreduction of non-productive operator time associated with repairingleaks that can occur from pressurizing/depressurizing multiple valvesand lines of the surface equipment. Beyond time and cost saving, theoperations can be safer, as personnel can remain out of the “red zone”and are not exposed to the related hazardous conditions.

A number of implementations of the have been described. Nevertheless, itwill be understood that various modifications may be made. Accordingly,other implementations are within the scope of the following claims.

What is claimed is:
 1. A method, comprising: pressurizing, using atleast a first fracturing pump, a first fluid line of a fracturingmanifold; while the first fluid line of the fracturing manifold ispressurized by at least the first fracturing pump: establishing a firstfluid coupling between a second fluid line and a first connector byeffecting relative movement between the second fluid line and the firstconnector, wherein the first connector is adapted to be in fluidcommunication with the first fluid line, and wherein the second fluidline is connected to, and extends from, a second fracturing pump; andremotely-controlling a first actuator to secure the first fluid couplingestablished between the second fluid line and the first connector; andafter securing the first fluid coupling, and while the first fluid lineof the fracturing manifold remains pressurized by at least the firstfracturing pump: discharging, using the second fracturing pump,pressurized fluid into the first fluid line via at least the secondfluid line and the first connector.
 2. The method of claim 1, whereinthe first connector is adapted to be in fluid communication with thefirst fluid line via a valve.
 3. The method of claim 1, wherein securingthe first fluid coupling comprises: moving, using the first actuator, alock profile into engagement with a corresponding profile associatedwith the second fluid line.
 4. The method of claim 1, furthercomprising: establishing a second fluid coupling between a fourth fluidline and a second connector by effecting relative movement between thefourth fluid line and the second connector, wherein the second connectoris adapted to be in fluid communication with a third fluid line of thefracturing manifold, and wherein the fourth fluid line is connected to,and extends from, the second fracturing pump; remotely-controlling asecond actuator to secure the second fluid coupling established betweenthe fourth fluid line and the second connector; and after securing thesecond fluid coupling: drawing, using the second fracturing pump, fluidfrom the third fluid line via at least the second connector and thefourth fluid line.
 5. The method of claim 4, further comprising:supporting the first and second connectors on a skid apart from thefracturing manifold.
 6. The method of claim 4, wherein the secondconnector is adapted to be in fluid communication with the third fluidline via a valve.
 7. The method of claim 4, wherein securing the secondfluid coupling comprises: moving, using the second actuator, a lockprofile into engagement with a corresponding profile associated with thefourth fluid line.
 8. The method of claim 4, wherein the second actuatoris not, does not include, and is not part of the first actuator.
 9. Themethod of claim 1, further comprising: supporting the second fracturingpump on a fracturing truck.
 10. A system, comprising: a first fracturingpump; a fracturing manifold including a first fluid line adapted to bepressurized by at least the first fracturing pump; a first connectoradapted to be in fluid communication with the first fluid line; a firstactuator; a second fracturing pump; and a second fluid line connectedto, and extending from, the second fracturing pump; wherein: while thefirst fluid line is pressurized by at least the first fracturing pump: afirst fluid coupling is adapted to be established between the secondfluid line and the first connector by effecting relative movementbetween the second fluid line and the first connector; and the firstactuator is adapted to be remotely-controlled to secure the first fluidcoupling established between the second fluid line and the firstconnector; and after the first fluid coupling is secured, and while thefirst fluid line remains pressurized by at least the first fracturingpump, the second fracturing pump is adapted to discharge pressurizedfluid into the first fluid line via at least the second fluid line andthe first connector.
 11. The system of claim 10, further comprising: alock profile; and a corresponding profile associated with the secondfluid line; wherein, to secure the first fluid coupling, the firstactuator is adapted to move the lock into engagement with thecorresponding profile.
 12. The system of claim 10, further comprising: avalve via which the first connector is adapted to be in fluidcommunication with the first fluid line.
 13. The system of claim 10,wherein the fracturing manifold further includes a third fluid line;wherein the system further comprises: a second connector adapted to bein fluid communication with the third fluid line; a second actuator; anda fourth fluid line connected to, and extending from, the secondfracturing pump; and wherein: a second fluid coupling is adapted to beestablished between the fourth fluid line and the second connector byeffecting relative movement between the fourth fluid line and the secondconnector; the second actuator is adapted to be remotely-controlled tosecure the second fluid coupling established between the fourth fluidline and the second connector; and after the second fluid coupling issecured, the second fracturing pump is adapted to draw fluid from thethird fluid line via at least the second connector and the fourth fluidline.
 14. The system of claim 13, further comprising: a skid apart fromthe fracturing manifold; wherein the first and second connectors aresupported on the skid.
 15. The system of claim 13, further comprising: alock profile; and a corresponding profile associated with the fourthfluid line; wherein, to secure the second fluid coupling, the secondactuator is adapted to move the lock profile into engagement with thecorresponding profile.
 16. The system of claim 13, further comprising: avalve via which the second connector is adapted to be in fluidcommunication with the third fluid line.
 17. The system of claim 13,wherein the second actuator is not, does not include, and is not part ofthe first actuator.
 18. The system of claim 10, further comprising: afracturing truck; wherein the second fracturing pump is supported on thefracturing truck.
 19. An apparatus, comprising: a first connectoradapted to be in fluid communication with a first fluid line of afracturing manifold, said first fluid line being adapted to bepressurized by at least a first fracturing pump; a first lock profile;and a first actuator adapted to move the first lock profile intoengagement with a first corresponding profile to secure a first fluidcoupling established between a second fluid line and the firstconnector, wherein the first corresponding profile is associated withthe second fluid line, wherein, while the first fluid line ispressurized by at least the first fracturing pump: the first fluidcoupling is adapted to be established between the second fluid line andthe first connector by effecting relative movement between the secondfluid line and the first connector; and the first actuator is adapted tobe remotely-controlled to secure the first fluid coupling, and whereinthe second fluid line is connected to, and extends from, a secondfracturing pump.
 20. The apparatus of claim 19, further comprising: thefirst fracturing pump; the first fluid line of the fracturing manifold;the second fracturing pump; and the second fluid line connected to, andextending from, the second fracturing pump.
 21. The apparatus of claim19, wherein, after the first fluid coupling is secured, and while thefirst fluid line remains pressurized by at least the first fracturingpump, the second fracturing pump is adapted to: discharge pressurizedfluid into the first fluid line via at least the second fluid line andthe first connector.
 22. The apparatus of claim 19, further comprising:a valve via which the first connector is adapted to be in fluidcommunication with the first fluid line of the fracturing manifold. 23.The apparatus of claim 19, further comprising: a second connectoradapted to be in fluid communication with a third fluid line of thefracturing manifold; and a second lock profile; and a second actuatoradapted to move the second lock profile into engagement with a secondcorresponding profile to secure a second fluid coupling establishedbetween a fourth fluid line and the second connector, wherein the secondcorresponding profile is associated with the fourth fluid line, wherein:the second fluid coupling is adapted to be established between thefourth fluid line and the second connector by effecting relativemovement between the fourth fluid line and the second connector; and thesecond actuator is adapted to be remotely-controlled to secure thesecond fluid coupling, and wherein the fourth fluid line is connectedto, and extends from, the second fracturing pump.
 24. The apparatus ofclaim 23, further comprising: the first fracturing pump; the first fluidline of the fracturing manifold; the second fracturing pump; the secondfluid line connected to, and extending from, the second fracturing pump;the third fluid line of the fracturing manifold; and the fourth fluidline connected to, and extending from, the second fracturing pump. 25.The apparatus of claim 23, wherein, after the second fluid coupling issecured, the second fracturing pump is adapted to: draw fluid from thethird fluid line of the fracturing manifold via at least the secondconnector and the fourth fluid line.
 26. The apparatus of claim 23,further comprising: a valve via which the second connector is adapted tobe in fluid communication with the third fluid line of the fracturingmanifold.
 27. The apparatus of claim 23, wherein the second actuator isnot, does not include, and is not part of, the first actuator.